This inventive subject matter relates to a powered system, such as a train, an off-highway vehicle, a marine, a transport vehicle, an agriculture vehicle, and/or a stationary powered system and, more particularly to a method and computer software code for determining a mission plan for a powered system when a desired parameter of the mission plan is unobtainable and/or exceeds a predefined limit so that optimized fuel efficiency, emission output, vehicle performance, infrastructure and environment mission performance of the diesel powered system is realized.
Some powered systems such as, but not limited to, off-highway vehicles, marine diesel powered propulsion plants, stationary diesel powered system, transport vehicles such as transport buses, agricultural vehicles, and rail vehicle systems or trains, are typically powered by one or more diesel power units, diesel-fueled power generating units, and/or. With respect to rail vehicle systems, a diesel power unit is usually a part of at least one locomotive powered by at least one diesel internal combustion engine and the train further includes a plurality of rail cars, such as freight cars. Usually more than one locomotive is provided wherein the locomotives are considered a locomotive consist. Locomotives are complex systems with numerous subsystems, with each subsystem being interdependent on other subsystems.
An operator is usually aboard a locomotive to insure the proper operation of the locomotive, and when there is a locomotive consist, the operator is usually aboard a lead locomotive. A locomotive consist is a group of locomotives that operate together in operating a train. In addition to ensuring proper operations of the locomotive, or locomotive consist, the operator also is responsible for determining operating speeds of the train and forces within the train that the locomotives are part of. To perform this function, the operator generally must have extensive experience with operating the locomotive and various trains over the specified terrain. This knowledge is needed to comply with prescribeable operating parameters, such as speeds, emissions and the like that may vary with the train location along the track. Moreover, the operator is also responsible for assuring in-train forces remain within acceptable limits.
In marine applications, an operator is usually aboard a marine vehicle to insure the proper operation of the vessel, and when there is a vessel consist, the lead operator is usually aboard a lead vessel. As with the locomotive example cited above, a vessel consist is a group of vessels that operate together in operating a combined mission. In addition to ensuring proper operations of the vessel, or vessel consist, the lead operator also is responsible for determining operating speeds of the consist and forces within the consist that the vessels are part of. To perform this function, the operator generally must have extensive experience with operating the vessel and various consists over the specified waterway or mission. This knowledge is needed to comply with prescribeable operating speeds and other mission parameters that may vary with the vessel location along the mission. Moreover, the operator is also responsible for assuring mission forces and location remain within acceptable limits.
In the case of multiple diesel power powered systems, which by way of example and limitation, may reside on a single vessel, power plant or vehicle or power plant sets, an operator is usually in command of the overall system to insure the proper operation of the system, and when there is a system consist, the operator is usually aboard a lead system. Defined generally, a system consist is a group of powered systems that operate together in meeting a mission. In addition to ensuring proper operations of the single system, or system consist, the operator also is responsible for determining operating parameters of the system set and forces within the set that the system are part of. To perform this function, the operator generally must have extensive experience with operating the system and various sets over the specified space and mission. This knowledge is needed to comply with prescribeable operating parameters and speeds that may vary with the system set location along the route. Moreover, the operator is also responsible for assuring in-set forces remain within acceptable limits.
Based on a particular train mission, when building a train, it is common practice to provide a range of locomotives in the train make-up to power the train, based in part on available locomotives with varied power and run trip mission history. This typically leads to a large variation of locomotive power available for an individual train. Additionally, for critical trains, such as Z-trains, backup power, typically backup locomotives, is typically provided to cover an event of equipment failure, and to ensure the train reaches its destination on time.
Furthermore, when building a train, locomotive emission outputs are usually determined by establishing a weighted average for total emission output based on the locomotives in the train while the train is in idle. These averages are expected to be below a certain emission output when the train is in idle. However, typically, there is no further determination made regarding the actual emission output while the train is in idle. Thus, though established calculation methods may suggest that the emission output is acceptable, in actuality the locomotive may be emitting more emissions than calculated.
When operating a train, train operators typically call for the same notch settings when operating the train, which in turn may lead to a large variation in fuel consumption and/or emission output, such as, but not limited to, NOx, CO2, etc., depending on a number of locomotives powering the train. Thus, the operator usually cannot operate the locomotives so that the fuel consumption is minimized and emission output is minimized for each trip since the size and loading of trains vary, and locomotives and their power availability may vary by model type.
However, with respect to a locomotive, even with knowledge to assure safe operation, the operator cannot usually operate the locomotive so that the fuel consumption and emissions is minimized for each trip. For example, other factors that must be considered may include emission output, operator's environmental conditions like noise/vibration, a weighted combination of fuel consumption and emissions output, etc. This is difficult to do since, as an example, the size and loading of trains vary, locomotives and their fuel/emissions characteristics are different, and weather and traffic conditions vary.
A train owner usually owns a plurality of trains wherein the trains operate over a network of railroad tracks. Because of the integration of multiple trains running concurrently within the network of railroad tracks, wherein scheduling issues must also be considered with respect to train operations, train owners would benefit from a way to optimize fuel efficiency and emission output so as to save on overall fuel consumption while minimizing emission output of multiple trains while meeting mission trip time constraints.
When planning a mission that may be performed autonomously, which includes little to no input from the operator, planning the mission may be difficult if the planning is not robust enough to accept various user inputs. In standard optimization theory, constraints are used to restrict the system to behave in a given way. However, this can lead to situations where a physically reasonable problem is rendered unsolvable because it is not strictly feasible given the mathematical constraints specified on the optimization problem. This can cause the whole optimization to fail. For example, with respect to a rail vehicle, to constrain the rail vehicle notch to behave smoothly, a rate limit may be imposed on the notch. However in exceptional cases, such as but not limited to abrupt grade variations, it may be impossible to satisfy this constraint while avoiding over speeding and/or stalling. In another example if a certain speed is imposed but the rail vehicle does not have sufficient power to reach the specified speed, the optimization may fail.
Owners and/or operators of rail vehicles, off-highway vehicles, marine powered propulsion plants, transportation vehicles, agricultural vehicles, and/or stationary diesel powered systems would appreciate the financial benefits realized when these diesel powered system produce optimize fuel efficiency, emission output, fleet efficiency, and mission parameter performance so as to save on overall fuel consumption while minimizing emission output while meeting operating constraints, such as but not limited to mission time constraints, where determining a mission plan is possible even when a desired parameter of the mission plan may be unobtainable and/or exceeds a predefined limit.